The use of seat belt restraining systems in vehicles for occupant restraint is well known in the prior art. In fact, many jurisdictions have enacted legislation requiring vehicle drivers or passengers to use seat belt restraining systems during vehicle operation.
One of the problems with seat belt restraining systems is injury to a vehicle occupant as a result of the restraining force of the seat belt rather than a vehicle collision. The force of a collision, particularly a head-on collision, pushes the vehicle occupant forward against the seat belt which is unyielding by virtue of its inertia locking or restraining system. The unyielding nature of the seat belt can cause injuries to the chest area of the vehicle occupant.
To overcome this problem, the prior art has devised different types of energy attenuating or energy absorbing devices in vehicle restraint systems.
In U.S. Pat. No. 4,674,801 to DiPaola et al., an energy absorber having a limited stroke is disclosed for use in a safety restraint system. The energy absorber includes a length of cable which is wound through a tubular ferrule, the cable including stop means on ends thereof. During a collision, the cable is pulled through the ferrule to absorb crash energy.
U.S. Pat. No. 3,289,792 to Moberg discloses an apparatus for absorption of energy from a moving load. The apparatus includes a shearing apparatus which provides a material to be shorn and plastically deformed for energy absorption.
U.S. Pat. No. 4,076,306 to Satzinger discloses a vehicle seat rest having a deformable section therein. The deformable section is made part of a rectangular seat frame and deforms under the influence of certain side forces.
However, these types of prior art devices are disadvantageous since they require complex mechanical arrangements that require interaction amongst various components and are costly to manufacture. Moreover, certain devices do not adequately dissipate or absorb energy in head-on collisions.
As such, a need has developed to provide an improved energy absorbing device for seat belt restraining systems that is low in cost, easy to manufacture and provides a safe and effective way to absorb energy during a head-on collision.
In response to this need, the present invention provides an energy absorbing beam for use with vehicle seat belt restraining systems that overcomes the drawbacks of prior art devices and provides effective energy dissipation when mounted to a seat or vehicle during head-on collisions.